This application relates to communication over a dedicated physical communication link used for point-to-point video communication, such as a coaxial cable, and specifically to upstream communication (in opposite direction to video transmission) over such links.
FIG. 1 shows a typical prior art arrangement in which a video sender, such as a video camera, sends a stream of video data to a video receiver, such as a Digital Video Recorder (DVR) over a dedicated physical link such as a coaxial cable. Such arrangements are common, for example in the form of Closed Circuit Television (CCTV) systems that are frequently used for security purposes. While networked cameras (e.g. using Internet Protocol (IP) for communication over an intranet, or the Internet) may be used for video communication, such networks tend to suffer from latency, may provide poor video quality, and raise security concerns. Furthermore, coaxial cables are already installed for point-to-point communication in many locations where their replacement would be costly and/or difficult. High Definition (HD) video with low latency is possible over such links, for example using the HDCCTV standard. However, while HDCCTV communication may allow use of existing physical links, it may require significant new hardware at each end (e.g. new cameras and DVRs) may be expensive to implement, and may have limited functionality and flexibility. Therefore, there is a need for improved systems and methods for using dedicated communication links for point-to-point communication.